Peristalsis within a gastro-intestinal (GI) tract may transport swallowed food and may aid in digestion and eventual evacuation. Peristalsis may result in pressure waves or contractions moving along the GI tract, thereby resulting in motility of a bolus or other object within the GI tract.
Certain pathological conditions may alter the normal motility within the GI tract. Low motility may be caused by, for example, an obstruction, a blockage, impaired motor activity, or other pathological condition. Motility disorders may be caused by, for example, nervous disorders, and may not necessarily be visible.
Abnormal intestinal motility may produce severe symptoms, such as chronic intestinal pseudo-obstruction. Known methods for diagnosis of intestinal motor disorders may be based on intestinal manometry, which may require prolonged intestinal intubations and/or intestinal histopathology on full thickness biopsies obtained by laparotomy or laparoscopy. Current evaluation of intestinal motility may relay on manometric detection of occlusive contractions, but these phasic events may account only for a minor fraction of recording time, and quiescence may be assumed by exclusion.
The analysis of intestinal dysfunctions generally requires invasive surgery in which a probe is introduced into the intestinal tract of a patient. The patient has to be hospitalized and the presence of qualified staff during the clinical intervention is required. Intestinal motility activity is one of the main sources of information which gastroenterologists have in order to assess the presence of certain intestinal dysfunctions. Motility assessment is generally performed by means invasive surgery, such as intestinal manometry.
Some in-vivo sensing systems may include an in-vivo imaging device able to acquire and transmit images of, for example, the GI tract while the in-vivo imaging device passes through the GI lumen.
Recently, a novel technique named capsule endoscopy has proved its efficiency as an alternative endoscopic technique. With capsule endoscopy, a pill with a micro-camera located inside it is swallowed by the patient. The capsule housing may incorporate an illumination source, power supply, and a radio-frequency transmitter to send, for example, a stream of image frames to an external device for storage and analysis. The capsule endoscope may be passively and/or naturally passed along the GI tract by for example peristaltic motion while capturing image frames from within the body lumen of, for example, the body lumen walls. As the pill traverses the gastrointestinal tract it takes pictures (images) thereof at a rate of a given number of frames per second.
The pictures are transmitted by means of radio communications to an external recording device where they are stored. The series of pictures taken as the pill traverses the gastrointestinal tract form frames of a video movie. The image frames captured may be, for example, downloaded into a workstation for review by specialists. In some examples, the image stream captured may be used for diagnostic purposes.
The use of capsule endoscopy analysis of the intestinal tract avoids the disadvantages of conventional invasive techniques. However, intestinal juices are often turbid with varying density, opacity and color and sometimes can be dense enough to block the whole field of view of the camera. In addition, intestinal juices may produce bubbles, which may differ in shape and color. Consequently, viewing of the video frames may be considerably hampered, if not impossible in some instances.
Turbid media, e.g. intestinal juices, may be present within the body lumen during image capturing. The turbid media may at times obstruct the field of view of the micro-camera so that some of the image frames captured may include an obstructed view of, for example, the body lumen wall.
Other devices, systems and methods for in-vivo sensing of passages or cavities within a body, and for sensing and gathering information (e.g., image information, pH information, temperature information, electrical impedance information, pressure information, etc.), are known in the art.